public class Radio {

 public String country{get;set;}
public  String[] countries{get;set;}
         
    public PageReference test() {
        return null;
    }
                
    public List<SelectOption> getItems() {
        List<SelectOption> options = new List<SelectOption>(); 
        options.add(new SelectOption('US','US')); 
        options.add(new SelectOption('CANADA','Canada')); 
        options.add(new SelectOption('MEXICO','Mexico'));
        options.add(new SelectOption('UK','UK'));
        return options; 
    }
                  
}